EN
The article deals with the common currency as one of the biggest challenges currently facing the European Union. Arising from the financial crisis 2008–2009 and deepened by Brexit, they ought to be interpreted and analyzed as the most important impulse to further integration, especially within the sphere of fiscal policy on supranational level. The author claims that for those EU member states which do not participate in the monetary union it is the optimal moment for the decision to join and initiate the relevant procedures. Without any decisions so called multi- or two speed Europe is to be considered as a political fact. For Poland such a scenario creates costly and uncertain position which could inhibit its activities in the common Europe.